Tetrakisazo dyes, and the process of manufacture



No Drawing.

Patented Jan. 25, 1927.

- UNITED STATES PATENT OFFICE} JOSEPH B. OESCH, F MILWAUKEE, WISCONSIN, ASSIGNOR TO THE NEWPORT COM- PANY, 0F CARROLLVILLE, WISCONSIN, A CORPORATION OF DELAWARE.

TETRAKISAZO DYES, AND THE PROCESS OF MANUFACTURE.

Application filed February molecular proportions of m-toluidine as mid- 6, 1926. Serial No. 86,656.

dle components, and one molecular proportion of an end component consisting of phenyl methyl pyr'azolone and its substitution products. 1

These new dyes correspond to the general formula The process of manufacture consists in combining an ammoazo dye of the benzene series with m-toluidine, diazotizing the in-' 1:onic acid sodium salt in 300 parts of water and diazotize at 05 C. by adding 6.9 parts of sodium nitrite. Then add this solution to 40 parts of hydrochloric acid B.), stir and correct excess nitrite. To the diazo compound add a solution of 11.2 parts of m-toluidine dissolved in 150 parts of water and 14 parts of hydrochloric acid (20 B.) Stir and add slowly a solution of 31 parts of sodium acetate, stirring until coupling is complete. Add 20 arts of sodium carbonate (1n solution) an 7 .3 partsof I N ii 7 I75 r som som NfN lute the filter cake with about 1000 parts of water and add 4 parts of sodium hydroxide.

Stir until complete solution is obtained; then add 7 parts of sodium nitrite and run the mixture into a solution of 35 parts of hydrochloric acid (20 B.) in 400 parts of water. Stir, correct excess nitrite, and add the diazo component to a solution of 26.2 parts of phenyl methyl pyrazolone sulfonic acid sodium' salt which has been previously dissolved in 31.8 parts of sodium carbonate and 200 parts of water. Stir and salt out, filter and 1 dry the filter cake.

The dye thus obtained corresponds to the following form'ulaz' In the shape of their salts, the dyes ofthis class are dark' powders, soluble in water to give brown solutions which change into reddish brown by the addition of caustic soda. \Vith hydrochloric acid the dyes separate as greenish brown precipitates. The a dye powders are insoluble in ether and partly soluble in alcohol and benzene. They dye cotton a yellowish brown.

Strong reducing agents split up the tetra-- kisazo structure, as indicated, to give in the case of the specific dye of the above example, the following reduction broducts:

o-toluidine-p-sull'onlc acid C NE S0;Na o-mothylo'-sulIonie-p-phenylonedlaminc H ISO H, H, v

methyl-p pheuyleuelliamiuc I (2 molecules) CI.[;

-;Na I am aware that numerous details of the process may be varied through a wide range without departing from the spirit of this invention, and I do not desire limiting the patent granted other than as necessitated by the prior art.

I claim as my invention: 4 1. As a new article of manufacture a tetrakisazo dye as hereindescribed, having most probably the following formula:

C OH

(80:11) 0 or 1 groups 3. The method of preparing a tetrakisazo dye of the general formula:

which consists in combining disulfonic acid with m-to uidine, diazotiz- (lOH aminoazotoluol ing the intermediate dye thus obtained,

combining the. same with m-toluidine, di-

6 in claim 1.

I body of the azotizing the trisazo dye and combining the 5. Materials dyed with the dye: described phenyl in claim 2. 3

6. The method of preparing a tetrakisazo with the dye described dye -of the general formula: 7

last mentioned compound vith methyl pyrazolone 'sulfom'c acid.

4. Materials dyed 8 lorigmupsv which consi in eombinin an amino azo finzene series ,w ith m-toluiiiine, diazotizing the intermediate dye thus obtained, cpmbiningv the same mth m-toluidine, diazotizing the trisazo dye and combining the last mentioned compound with phenyl methyl pyrazolone.

JOSEPH B. onscn. 

